Channel radiation X-ray laser

Summary form only given. A program concerning the development of an X-ray laser based on radiation due to quantized transverse oscillations of a relativistic electron traversing a crystal channel is discussed. Photons emitted from transitions between the transverse energy levels will have their energy Doppler upshifted, and, depending on the crystal, X-ray wavelengths can be generated for several MeV electron energies. Either planar or axial channeling of the electrons can be used. As an example, for diamond and assuming axial channeling along the <100> axis, /spl sim/3 keV photons are produced from a /spl sim/3.5 MeV electron. Essential features of this laser are Bragg reflection, distributed feedback and the Borrmann anomalous transmission effect to reduce absorption. These phenomena reduce the gain requirements. The channel radiation gain is mainly determined by the properties of the electron beam. A current density of the order of 10/sup 6 A/cm/sup 2/ and total current of several milliamperes is required for gain, and the transverse energy must be less than /spl sim/10 eV. The required beam brightness is of order of 10/sup 9/ A/cm/sup 2/ - rad/sup 2/.